Washer with reversing spray assembly



Dec. 8, 1964 Filed Oct. 3, 1963 F. e. CONSTANCE ETAL 3,160,164

WASHER WITH REVERSING SPRAY ASSEMBLY 8 Sheets-Sheet 1 FIG. 10

INVENTORS. FREDERICK G. CONSTANCE 8 IIQBIYQHARD L. PERL 0%;Wu/iye fwd?ATTORNEYS Dec. 8, 1964 F. G. CONSTANCE ETAL 3,160,164

WASHER WITH REVERSING SPRAY ASSEMBLY Filed 00$- 3, 1965 8 Sheets-Sheet 2Fl G. 2

I0 I38 I2 [70 s4 I :11::1 I56 v INVENTORS. FREDERICK e. CONSTANCE a 1..PERL I ATTORNEYS Dec. 8, 1964 F. a. CONSTANCE ETAL 3,160,164

WASHER WITH REVERSING SPRAY ASSEMBLY Filed Oct. 3, 1963 a Sheets-Sheet sFIG.3

RICHARD L. PERL. BY M,77Zm?eflwme@ ATTORNEYS Dec. 1964 F. 5. CONSTANCEETAL 3,160,164

WASHER WITH REVERSING SPRAY ASSEMBLY 8 Sheets-Sheet 4 Filed Oct. 3, 19633 w OE a v 1 R 09 com mouvloa INVENTORS. FREDERICK G. CONSTANCE &RICHARD L. PERL ATTORNEYS 1964 F. G CONSTANCE ETAL 3,150,164

WASHER WITH REVERSING SPRAY ASSEMBLY Filed 001;. 3, 1963 8 Sheets-Sheet5 FIG. 9

174a I84 I52 INVENTORS. FREDERICK G. CONSTANCE 8 RICHARD L. PERLATTORNEYS 1964 F. G. CONSTANCE ETAL 3,160,

WASHER WITH REVERSING SPRAY ASSEMBLY Filed Oct. 3, 1963 8 Sheets-Sheet 6FIG. 72 I76 3 ROTATION 4 II N [I I 248 /I |54 1 w 282 INVENTORS.

250 gRgDERACIB COENRiTANCE H /1 /)s///// y ATTORNEYS Dec. 8, 1964 F. G.coNsTANcE ETAL 3,160,164

WASHER WITH REVERSING SPRAY ASSEMBLY 8 Sheets-Sheet 7 Filed Oct. 3, 1963INVENTORS.

FREDERICK G. CONSTANCE a RICHARD L. PERL 1 NOLLVlOH ATTO R NEYS awaits"I Fatented Dec. 8, 1964 3,l-iit,l64 WASHER WITH REVERSING SPRAY ASSEMBLYFrederick G. Constance and Richard L. Perl, Mansfield, Ghio, assignorsto The Tappan Company, Mansfield, Ghio, a corporation of @hio Filed Oct.3. 1963. Ser. No. 313,534

22 Claims. (Cl. 134-176) This invention relates in general to washingmachines and devices, such as dishwashers, in which a reversing spray ofwater or cleaning solution is desired for varying distribution of thespray, and relates more particularly to improved spray mechanism inwhich such a reversal is automatically effected in the normal operatingcycle thereof.

In washers, for example dishwashers, provided with directional sprayarms of the so-called reaction type, fluid under pressure enters theinterior of the spray arm and flows outwardly thereof through drive jetsor openings which are inclined relaitve to the vertical, the pressure ofthe fluid directed outwardly through the jets creating a reaction forcecausing rotation of the arm in a direction opposite to that of the jetspray. In washers of the described type a spray pattern is createdwhich, stated in a somewhat oversimplified way, comprises generallyvertical and horizontal spray components producing an inclineddirectional spray. Such a spray pattern often results in less thansatisfactory washing since the dishes or other tableware in the washingchamber are thus subjected to the spray substantially only at one sidein any sense of direct scouring impingement.

A primary object of the present invention, therefore, is to achieve anew and superior liquid spraying action by providing a spray arm thedirection of rotation of which is reversed automatically to createvarying spray patterns and thereby achieve greater distribution of theliquid as projec ed by said arm.

A further object of the invention is to provide such a dishwashingmachine having such a spray arm therein so that the noted reversingaction provides washing and rinsing of all surfaces of the dishes andutensils to be cleansed in the machine.

A further object of the present invention is to provide a reversingspray arm wherein there is a relative radial shifting of the points oforigin of the spray responsive to changes in directions of rotation ofthe spray arm thereby to provide a highly effective spray pattern.

A further object resides in providing such automatic reversal of the newspray arm in response to changes in the fluid pressure of the liquidbeing discharged through the spray arm.

A further object of the present invention is to provide a highlysimplified spray arm construction wherein the means for reversing therotation of the spray arm responsive to a drop in fluid pressurecomprises relatively few component parts thereby substantially reducingproblems of malfunction and/ or replacement.

These and other objects and advantages of the present invention willbecome apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention,then, comprises the features hereinafter fully described andparticularly pointed out in the claims, the following description andthe annexed drawings setting forth in detail certain illustrativeembodiments of the invention, these being indicative, however, of but afew of the various ways in which the principle of the invention may beemployed. 7

In said annexed drawings:

FIG. 1 is a front elevational views, partly broken away and sectioned,of a dishwasher having a pair of vertically spaced spray arm assembliesconstructed in accordance with the, present invention;

FIG. 2 is a side elevational view, similarly partly broken away andsectioned, of such dishwasher;

FIG. 3 is a horizontal sectional view taken on section line 33 of FIG.1;

FIG. 4 is an enlarged fragmentary plan view of one form of spray armassembly of the invention;

FIG. 5 is a vertical sectional View taken through the spray arm assemblyof FIG. 4, on section line 5-5 thereof;

FIG. 6 is a sectional view taken on line 6-6 of FIG. 5, on an enlargedscale;

FIG. 7 is a sectional view taken on line 7-7 of FIG. 5;

FIG. 8 is a sectional view taken on line 8-8 of FIG. 5;

FIG. 9 is a partially sectioned view of the fluid flow control mechanismof the spray arm assembly illustrated in FIGS. 4-8;

FIG. 10 is a fragmentary perspective view of such fluid flow controlmechanism;

FIG. 11 is a fragmentary top plan view, partially sectioned, of analternative form of spray arm assembly;

FIG. 12 is a sectional view of such alternative form spray arm assembly,taken on lines 1212 of FIG. 11;

FIG. 13 is a sectional view taken on lines 13-13 of FIG. 11;

FIG. 14 is a sectional view taken on lines 14-14 of FIG. 13;

FIG. 15 is a perspective, exploded view of the fluid flow controlmechanism of the alternative embodiment illustrated in FIGS. 11-14;

FIG. 16 is a top plan view of another alternative form of spray armassembly;

FIG. 17 is an enlarged top plan view, partially broken away, of thefluid control mechanism of the alternative, FIG. 16 form of spray armassembly;

FIG. 18 is an enlarged, exploded view of the fluid control mechanism ofthe FIG. 16 embodiment;

FIG. 19 is a longitudinal vertical sectional view taken on lines 19l9 ofFIG. 16;

FIG. 20 is a transverse vertical sectional view taken on lines 2tl2t) ofFIG. 16;

FIG. 21 is a fragmentary, plan view of another form of spray armassembly, with the top of the housing partially removed to illustratethe fluid control mechanism; and

FIG. 22 is a longitudinal vertical sectional view of the FIG. 21 form ofthe invention, taken on lines 2222 thereof.

Referring now to the drawings in detail, and initially to FIGS. 1-3, thedishwasher embodying the present invention comprises a cabinet generallyindicated at 10 within which a tub or chest 12 is suitably supported toform a washing chamber 14. The cabinet and tub are both open at thefront and are adapted to be closed by a bottom hinged door 16 which ispivotally mounted at the front of the cabinet as indicated at 18 formovement between a vertical, closed position and a substantiallyhorizontal, open position, the latter such position being shown indotted lines in FIG. 2 providing access to the interior of the tub 12.The door 16 includes a hand grip portion preferably at the top thereoffor opening and closing the door in the usual manner. Suitable sealingstrips, the top sealing strip being shown at 22, are provided at thesides for sealing the door when closed.

Upper and lower racks 24 and 26, respectively, shown in dashed lines inFIG. 1, are disposed within the tub 12 for holding tableware, utensils,and the like, also indicated in dashed lines in FIG. 1. In the usualmanner, which forms no part of the present invention, the racks 24 and26 are provided with guide rollers or the like at the sides thereof forrolling engagement with supporting and guiding structure mounted on thesides of the tub whereby the racks can be rolled from the tub forconvenient loading and unloading. As will be hereinafter morespecifically described, the upper rack 24 is disposed above the topspray arm assembly and the lower rack 26 is disposed between the top andbottom spray arm assemblies.

The tub 12 is provided with a sloped bottom 23 the lowest portion ofwhich is in the form of a depressed sump 30 having an open top adaptedto be covered by a filter element generally indicated at 32. Referringjointly to FIGS. 1 audit, the filter element 3-2 is providedwith ahandle 34 for removing the same for cleaning'thereof, and furtherincludes a dish-shaped body portion 36 of relatively fine filter screenmaterial having apertures 33 provided therein which trap the foodparticles and allow recirculation of only generally particle-freesolution. The filter 32 further includes a peripheral flange ifiadaptedto seat on a complemental peripheral flange member 42 formed in the topof the sump 3% The solution drains from the tub through a plurality ofspaced holes 44 which extend around the top of the filter elementinwardly of i the flange 42 whereby the solution drains into the sump 30as indicated by the arrows in FIG. 1. The solution passing upwardlythrough the relatively fine openings 38 drains from the filter 32through a recirculating drain pipe 46 suitably secured to and dependingfrom the bottom of such filter element. The drain pipe 46 is adapted totelescope within a pipe-receiving upper end 50 of a hose member 52 whichleads to the input side of a circulating pump generally indicated at 54.The sump further includes a drain outlet 56 through which the particlesnot passing through the filter element are adapted to be drained. Adrain hose 58 is suitably connected to the drain opening 56, theopposite end of such hose communicating with the inlet of a drain pumpgenerally indicated at 66, the latter pumping the drained solution to asuitable discharge point in a well-known manner.

' A water fill hose (not shown) is provided for supplying water to thewashing chamber 14, the usual air gap being provided between the hoseand water-receiving means on the machine. Such water fill hose can bemounted adjacent the tub 14 in any suitable location, for examplerelatively adjacent'the top wall thereof for water flow over the dishesand utensils during the pro-wash cycle.

An electric heating element 62' irregularly shaped as shown is mountedadjacent the bottom of the tub, the terminal ends 64 and 66 of theheating element 62 extending from the cabinet rear wall and beingconnected to a suitable current source whereby such heating element isadapted to heat the water or solution in the region thereabout.

It will thus be seen that in the invention thus far described watersupplied to the washing chamber 14 will drain toward the sump 3G and theportion thereof sutficiently free from entrained solids will passthrough the apertures 38 into the recirculating drain pipe 46 and thusto the hose 52 leading'to the circulating pump 54. If there is nopro-wash cycle, the entire supply of water will of course pass to thepump 54. Responsive to control apparatus provided with the dishwasherand forming no part of thepresent invention, the circulating pump 54will circulate water to the upper and lower spray arms briefiy referredto above and generally indicated at 7%) and 72, respectively, theconstruction and operation of which will be hereinafter specificallydescribed. The water emanating from the spray arms '76 and 72 willthoroughly wash the tableware and utensils in the Washing chamber 14,such solution ultimately gravitating to the bottom of the tub and to thesump 30. As previously described, food particles of a size in excess ofthe size of the openings 38 Will pass through the sump drain 56 to thedrain pump 60 for ultimate discharge.

The discharge outlet'76 of the circulating pump 54 has connected theretoa center hose '78 axially through which water is supplied directly tothe lower spray arm '72 as will be hereinafter described. The centerhose 73 is provided with an opening in a side wall thereof adapted toreceive a hose 82 for supplying fluid to the upper spray arm 7% Theopposite end portion of such hose 32 is suitably mounted at its upperend to the back of the tub 12, a peripheral flange 84 being preferablyprovided at such end of the hose which is clamped between the tub rearwall and the cantilevered tubular mounting member generally indicated at86 for the upper spray arm 70. As shown in FIG. 2, mounting meansindicated at 33 are provided for mounting such member on the rear wallof the tub 12 as will be hereinafter described. It will accordingly beseen that Water or solution discharged from the circulating pump 54 willflow upwardly therefrom through the center hose 78 to the lower sprayarm 72 and to the upper spray arm 70 through the hose 82.

Referring now to the manner in which the lower spray arm '72 isrotatably mounted adjacent the bottom of the tub 12, most clearly shownin FIG. 5, the sloped tub bottom 28 is formed with a central elevatedarea 92' the top of which is in the form of a horizontally disposedannular mounting flange 92 provided with a central opening ran, thediameter of such opening corresponding with the inside diameter of thecenter hose 78. The center hose '73 is formed with an outwardlyextending top annular flange 1632 which abuts the bottom surface of theflange 92. A plate rsa having an inwardly directed flange 1% whichunderlies the flange iii-2 abuts the bottom of the flange 92 and is heldin this position by means of a plurality of bolts lllti, only one ofwhich is shown in FIG. 5, which extend downwardly through openingsformed in center. post mounting member llltl. The mounting member 119 isprovided with a central cylindrical portion 112 which telescopes withinthe center hose 78 and further includes a plurality of arcuately spacedspider elements 114, only one of which'is visible in FIG. 5, whichcentrally define .a threaded opening 116 adapted to receive a spray armmounting knob generally indicated at 118, as will be hereinafter furtherdescribed. The combined hori- Zontal cross-sectional area of theelements 14 does not materially affect fluid flow upwardly therethrough.

The mounting member 116 is formed with an annular groove 120 for seatingengagement with a center post generally indicated at 122. The centerpost includes a cylindrical central portion 124 through which themounting knob 118 extends, a plurality of spider arms 126 rigidlyconnected thereto, and an outer cylindrical ring portion 128 preferablyintegrally formed with the spiders 126, the bottom of such ring portionseating in the abovedescribed groove 126 in the mounting member lid. Thecenter post is maintained in such assembled position by means of themounting knob 118.

An actuating pin 134) is rigidly mounted to the center post 122 adjacentthe periphery thereof and extends upwardlytherefrom to a heightapproximating the height of the spiders 126. In a manner to be morespecifically described hereinbelow, the actuating pin 13%) functions tocondition the spray arm assembly for automatic reversal in direction ofrotation.

It will thus be seen that the center hose 78, the center post mountingmember 119 and the center post 122 form a rigidly connected assemblythrough which water directed upwardly through the center hose "7% can beeffectively supplied to the spray arm assembly 72.

The upper spray arm 70 is mounted on the inner end 87 of the tubularmounting member 86 in much the same manner as the mounting for the lowerspray arm 72. The inner end 87 thereof thus receives the center post(not shown), which in turn rotatably mounts the spray arm 70, the latterbeing retained thereon by means of mounting knob 134.

The upper and lower spray arm assemblies 76 and '72, respectively, areidentically constructedand accordingly only one need be described indetail. As best shown in FIGS. 4-10, the lower spray arm '72 comprises ahousing generally indicated at 156 which is in the form shown preferablyplastic and comprises upper and lower mating housing sections 152 and154, respectively. Each of said upper and lower sections is formedwith'a plurality of peripherally spaced embossed portions commonlydesignated at 156 through which suitable securing means, for examplebolt means, commonly designated at 1558, are adapted to extend intothreaded engagement with tapped openings in the lower section 154 forassembly of the section in the manner indicated to provide a tubularhousmg. i

The upper housing section 152 is formed with a central opening 16%which, then the mounting bolt 118 is removed from threaded engagementwith the mounting member 11% is adapted to fit over the cylindricalcentral portion 124 of the center post, the top surface of the spiders1126 serving to support the upper section in such position. The bottomsection 3154 is similarly provided with a centrally disposed opening 162for positioning such lower section around the ring portion 128 of thecenter post. The housing is thus supported for rotation at the top andbottom thereof. A pair of bearing washers led and 166 are provided oneither side of the upper section 15?; around the central openingtherein.

One end of the housing 15%, the left end as viewed in FIGS. 4-6, isprovided with a series of radially spaced drive jets or openings, onerow of which is commonly designated at 1'79, disposed on one side of avertical plane passing through the longitudinal axis of the spray arm,These drive jets 176 are directed outwardly and upwardly relative to thehousing, as clearly shown in FIG. 7. A series of radially staggered,oppositely directed spray jets or openings commonly designated at 172are provided on the opposite side of such plane passing through thelongitudinal axis, the openings 172 likewise being directed upwardly andoutwardly relative to the housing. in a manner well understood to thosein the art, the provision of such drive jets provides a reaction typespray arm rotation wherein water directed to the housing and outwardlythrough either of the set of the jets 17th or 172 will serve to drivethe spray arm in a direction opposite to the horizontal component of theinclined jets. This directional relationship is clearly shown in FIG. 6wherein the fluid is shown emanating through the drive jets 172 andwherein the spray arm 156 is shown as rotating in the opposite,clockwise rotation.

That end of the spray arm housing 15b formed with the drive jets 17d and172 is provided with a longitudinally extending partition 174 forseparating the housing into two chambers are and 173, the former chambercommunicating with the washing chamber 14 through the drive jets 17d andthe latter chamber communicating with the washing chamber through thedrive jets 172. As will be apparent, fluid is alternately supplied toeither chamber 176 or chamber 178 for driving the spray arm in oppositedirections.

A transversely extending partition 1% defines the inner bounds of thechambers 176 and 178, such partition being provided with spaced ports182 and 184 for alternately supplying fluid to the chambers 176 and 178,respectively. The ports 182 and 184 are preferably provided with beveledsurfaces commonly designated at I186 to enhance the seating of a ballvalve 1% of a ball valve assembly or mechanism generally indicated at192. The ball 19% alternately seats on the beveled surfaces 1% of theports 182 and 184 to alternately close the respective chambers 17d and178 to liquid flow through these ports, as will be further describedhereinbelow.

The opposite end of the spray arm housing 150 is in the form shownprovided with a series of spaced, vertically disposed non-drive jets oropenings Ztlt). As clearly seen in FIG. 8, the inner end of the housingcontaining the non-drive jets 2th is completely open thus comprisb7 ingbut a single fluid chamber 202. Although in the form shown, drive jetsare provided on only one side of the spray arm, it should be understoodthat drive jets could be provided on both sides of the spray arm aswell.

Referring now to the detailed construction of the ball valve assembly192, a bar member 210 is pivotally mounted on the transverse partition18% by means of a mounting screw 212, the latter extending through thepartition 18% into a threaded opening in the longitudinal partitionmember 174. The bar Zll) serves as a ramp down which the ball 1% canmove to positions adjacent ports 182 or 184- under conditions to bedescribed hereinbelow. To prevent the ball 19% from sliding off the sideof the bar 216, a guide railZl i is provided, the opposite ends of whichare firmly secured in the sides of the housing section 152, as shown inFIG. 9.

A bar actuating member 226 is pivotally mounted on an embossed section222 of the bottom of the housing section 154 by means of screw 224. Thebar actuator 22% includes a preferably vertically oriented flexibleinner end 226 which, during rotation of the spray arm, contacts theactuating pin 13% of the center post. The opposite end of the baractuating member 220 is bent downwardly as indicated at 228 andterminates in an upwardly inclined resilient end portion 230 whichengages the bottom of the bar Zlt) and continually biases the sameupwardly about mounting screw 212. Thus, in the FIGS. 9 and 10 positionof the valve assembly, the end 239 biases the bar 219 about the screw212, the bar Zltl being refrained from so pivoting, however, by thewater pressure acting against the ball 1% and seating the same to closethe port 132, as will be further described hereinbelow. The bottom ofthe bar 210 is provided with pins 232 and 234 which serve to limit thepivotal movement in either direction of the bar actuating member 220.

The ball valve assembly functions to reverse the spray arm rotationresponsive to a drop in pressure within the housing 159. Such a drop inpressure occurs with each cycle change, as controlled by the timedcontrols provided with the dishwasher as previously described and whichform no part of the present invention. To provide a specific example,presume that the FIG. 10 showing of the valve assembly represents thepositioning of the various members during a washing cycle. The fluidcirculated by the circulating pump ddflows upwardly through the centerhose 78 to the spray arms 7%) and '72, the fluid flowing to the latterthrough the center post and mounting structure therefor and into thehousing 15%. A portion of the fluid flow directed to the housing 15thwill flow to the chamber 2% and outwardly therefrom through thevertically disposed non-drive jets 2%. The remainder of the fluid isdirected toward that end of the housing 159 having the drive jets 1'70and 172, and as the fluid under pressure enters such housing end, theball 1% is forced by such fluid to seat against and thus close the port182. As the fiuid pressure seats theball 1% against the beveled surface186 of the port 1252 thereby closing the latter, the fluid will bedirected through the opposite port 134 and thence outwardly through thedrive jets 172 whereby the spray arm will rotate in a clockwisedirection, referring to the FIGS. 6 and 10 orientation thereof. As thespray arm rotates in a clockwise direction about the vertical axisthereof, the inner flexible end 226 of the bar actuating member 22% willcontact the stationary actuating pin 13% during each revolution. Thus,following the first revolution and thereafter, the bar actuator 22%)will be biased by the actuating pin 139 to a position wherein theopposite end 230 thereof will underlie the bar 210 in a region thereofbelow the port 182 and the ball valve 199 seated thereagainst. Aspreviously described, this opposite end 230 biases the bar 219 upwardlyabout mounting screw 212, or counterclockwise as viewed in FIGS. 9 and10. The force exerted by the end 239 of the bar actuator 229 is,however, less than the force of the fluid pressure within the housingacting on the ball 199 and seating the same 7 to close the port 182.Thus, while this fluid pressure is maintained, the bar actuator 22%)will not exert a force suflicient to unseat the ball 190.

As soon as the fluid pressure within the housing drops off, for exampleat the end of such Washing cycle, the force of the bar actuator 22%, andmore particularly the end 230 thereof which engages and biases upwardlythe bottom of the bar 210, will, at a certain point, exceed the pressureof the fluid Within the housing, at which time the end 2361 of the baractuator 220 will cause the bar 210 to pivot about the mounting screw212 thereby unseating the ball valve 1% from the beveled valve seat 186of the port 182. The ball 1% will then roll down the bar 212, as shownby dashed lines in FIG. 9, to a position approximately below the port184. The bar actuator 220 will remain in its FIG. 10 position until thespray arm is rotated in the opposite direction.

At the commencement of another washing or rinsing cycle, fluid is againsupplied to the housing in the above-described manner and such fluidunder pressure will eflect a seating of the ball valve 190 against thebeveled valve seat 186 of the port 184 whereby the fluid entering thatportion of the housing 159 containing the valve assembly will bedirected through the port 182 into the chamber 176. Such pressurizedfluid will be directed outwardly through the drive jets 17% therebyrotating the spray arm in the opposite direction, or in acounterclockwise direction as viewed in FIGS. 6 and 10. Subsequent tothe first revolution, the inner end 226 of the bar actuator 220 willcontact the stationary actuating pin 134) during each revolution of thespray arm and such contact will cause the bar actuator 229 to pivotabout the pivot 224 to a position underlying the opposite end of the bar216 and approximately beneath the closed port 184, such pivotal movementbeing limited by the limit pin 234. AS previously described, the forceof the resilient end portion 230 of the actuator 220 is ineffective tounseat the ball 13% until a subsequent drop in fluid pressure in thehousing. The bar actuator 220 will be maintained in this position aslong as the spray arm continues to rotate in a counterclockwisedirection, reference again being made to the FIGS. 6 and 10 orientationthereof. As soon as, the pressure within the housing 150 becomes lessthan the force of the end 23d of the actuator bar 22% acting upwardlyagainst the bottom of the bar 210, the ball valve 190 will be unseatedand the bar 210 will be pivoted about mounting screw 212 to its FIGS.910 position, at which time the ball 1% will roll down the bar to aposition below the port 182.

In this manner the direction of rotation of the spray arm can bereversed in a very simple manner and through purely mechanical means,such reversal being responsive to a decrease in fluid pressure withinthe spray arm. Moreover, the reversal is etfected automatically by therotation of the spray arm, the biasing of the valve during such rotationbeing inetfective until a decrease in fluid pressure within the sprayarm at the end of the cycle. There will thus be a reversing of the sprayarm at the end of each cycle, there normally being a plurality of suchcycles in each cleansing operation. In this manner the tableware andutensils will be thoroughly washed on both sides thereof by the drivejets 179 and 172, such cleansing action being supplemented by thenon-drive jets which function to continually direct fluid upwardly intothe washing chamber 14. It should further be noted that by radiallystaggering the drive jets 170 and 172, a relative shifting of the pointsof origin of the spray is eflected whereby the spray is radially variedduring each direction of rotation. This arrangement results in a muchimproved spray patttern not obtainable in conventional, directional typespray arms.

Although the above discussion was directed to the construction andoperation of the lower spray arm 72, it will be understood that, aspreviously described, the internal construction and the operation of theupper spray arm 7% is the same as that described for the lower spray arm72, whereby a further description is not needed. It will be apparent,moreover, that the upper spray arm 76 can be made to rotate in the samedirection as the lower spray arm 72, or in the opposite directionthereof.

There is illustrated in FIGS. 11-15 a second embodiment of the presentinvention, such embodiment also comprising a spray arm reversible indirection responsive to a drop in fluid pressure in the housing 150.Where applicable, identical reference characters have been used forstructure which has been previously described relative to the firstdescribed embodiment. Thus, the center post construction and mounting isidentical, and with one exception the construction of the housing 150 isidentical to that above described. The housing in the FIGS. 11-15embodiment, referring to FIG. 11, is provided with a transversepartition 2% having ports 242 and 244 which communicate with thechambers 176 and 178, respectively. The inner end of the partition 24-0is formed with oppositely inclined surfaces 246 and 248 against whichvalve plate members 256 and 252, respectively, are adapted toalternately contact, such valve plate members forming part of a vmveassembly generally indicated at 254. Thus, in the FIG. 11 showing, thevalve plate 250 is shown in contact with the inclined surface 246 andclosing the port 242 whereby the fluid is directed through port 244 tothe chamber 178. The valve plates 250 and 252, as will be evidentalternatively open and close the ports 242 and 244, respectively.

The transverse partition 24% is provided with a vertical groove 25%Within which the valve assembly 254 is rotatably mounted. Referring morespecifically to the valve assembly, an exploded view of which is shownin FIG. 15, the plates 250 and 252 [are rigidly secured to cylinder 262,the latter being mounted for rotation within the groove 26% by means ofa pin 264, the opposite ends of which are loosely received in openingsprovided therefor in the upper and lower housing sections 152 and 154,as seen in FIG. 12. A valve plate actuating member generally indicatedat 270 is also pivotally mounted about the pin 264, the plate actuatorbeing provided with a raised, apertured section 272 through which thepin 264 extends. The plate actuator 270 further includes the flat bodyportion 274 and a bifurcated pin engaging member 276 mounted in anysuitable manner on the body portion 274 and extending upwardlytherefrom. The member 276 comprises arms 278 and 280 adapted to bealternately engageable with the actuating pin of the center post 122. Aspring member 282 is disposed between the body portion 274 and thecylinder 262, the spring telescoping around the raised section 272 andhaving an end convolution 234 adapted to be secured to the flat body274. The opposite end convolutions of the spring 282 telescope aroundthe cylinder 262, and the end 2% thereof is secured thereto. The spring282 thus serves to space the cylinder 262, and thus the plates 250 and252, from the actuator body 274 and biases the plate actuator 270downwardly against the housing bottom. In addition, the spring 282serves to bias or cook the valve plates in a manner to be morespecifically described hereinbelow. The'bottom of the housing section154 is provided with a raised or embossed portion 288 which functions toprovide over center action for the plate actuating member 270, the body274 of the latter being provided with upwardly curved sections at theside thereof to facilitate movement of the member 270 over the embossedportion 288.

Referring to FIG. 11, when fluid is supplied to the housing when thevalve assembly 254 is in a solid line position therein, such fluid willbe directed through port 244 to chamber 178 and thence outwardlytherefrom through the drive jets 172, whereby the spray arm '72 willrotate in a clockwise direction about the axis of the center post, allas indicated by arrows in FIG. 11. In such condition, the valve plate252 is disposed approximately midway between the inclined surfaces 246and 248. As the spray arm rotates, the arm 280 engages the stationaryactuating pin 13% whereby the plate actuating member 270 will be pivotedclockwise about the pin 246 to its solid line, FIG. 11 position therebycocking the spring 282. Due to the over center action provided by theraised section 288 of the housing, the actuator 270 will remain in suchposition until the spray arm is reversed in rotation as will bedescribed hereinbelow. The pivotal movement of the plate actuator 274)will not at this time effect an unseating of the plate 256 from theengagement with the surface 246 due to the fluid pressure within thehousing exceeding the force of the'cocked spring 282.

When the fluid pressure within the housing 150 drops, for example at theend of a cycle as previously described, the force of the spring 232 willeventually exceed the fluid pressure acting against the valve plate 250at which time the spring will force the plate 250 out of contact Withthe inclined surface 246. The spring 282 will simultaneously bias thevalve plate 252 toward the inclined surface 248 and thus effect aclosing of the port 244, such condition being shown in dashed lines inFIG. 11. The valve plate 250 will at this time assume a positionsubstantially in alignment with the previously indicated position of thevalve plate 252 approximately midway between the inclined surfaces 246and 243. The plate actuating member 27d will of course remain in itssolid line position until the direction of the spray arm 72 is reversed.

At the initiation of the next cycle, water introduced into the housing159 will be directed through port 242 and thence through the drive jets170 whereby the spray arm 72 will be driven in a counterclockwisedirection, reference again being made of FIG. 11. As the spray armrotates in a counterclockwise direction, the arm 27% will contact thestationary actuating pin 139 and the plate actuating member 270 will bepivoted about pin 264 to the dashed line position shown in FIG. 11.During each subsequent revolution of the spray arm, the arm 280 willcontact the actuating pin thereby maintaining the plate actuating memberin its dashed line, FIG. 11 position. As the plate actuating member 27%is moved to its dashed line position as a result of the arms 278 and 280contacting the stationary actuating pin 130, the spring 282 will becocked in a manner previously described where by the valve plate 252will be biased away from contact with the inclined surface 248. However,as long as the cycle continues, the fluid pressure within the housingacting against the valve plate 252 will exceed the pressure of thespring 282 whereby the valve plate 252 will be maintained in a positionclosing the port 244.

When the fluid pressure decreases within the housing at the end of thecycle, the force of the spring 232 Will bias the valve plate 252 awayfrom the port 244 thereby opening the same and pivoting the valve plates250 and 252 back to their solid line, FIG. 11 position. In this mannerthe rotation of the spray arm is continually reversed in directionresponsive to a decrease in fluid pressure.

Although the opposite end of the spray arm 72 has not been shown inFIGS. 11-15, it will be understood that such opposite end may beprovided with non-drive jets of the type illustrated at 200 in theembodiment above described in reference to FIGS. 410, or, additionaldrive jets may be provided in such opposite end.

A third form of the present invention is illustrated in FIGS. 1620, andthis form of the invention similarly provides for reversal of thedirection of rotation of the spray arm responsive to a decrease inpressure within the spray arm housing. This further form, however,differs from those previously illustrated in that drive jets are formedin both ends of the spray arm housing and there is accordingly providedfluid control means, associated with both of said ends for controllingthe fluid directed into the spray arm housing. The FIGS. 16-20 formfurther distinguishes those forms previously described that a differentarrangement is employed for cocking or torque loading the controlmechanism for automatic reversal upon a drop in pressure within thespray arm housing.

The E68. 1620 form comprises a spray arm housing 3% including upper andlower housing sections 392 and 3%, respectively. The upper and lowersections are preferably secured together by mounting bolts as previouslydescribed. Drive jets collectively referenced at 308 are pro dried onboth ends of the spray arm housing, the drive jets being directedupwardly and outwardly in the manner previously described. There areadditionally provided radially and circumferentially spaced non-drivejets collectively designated at 31th in the central portion of thehousing for providing additional spray to the washing chamber. It willbe noted that the driving jets 368 are radially offset so as to providevarying spray patterns for each direction of rotation.

Vertically extending partitions 312 and 314 are formed in the ends ofthe housing Still, the partition 312 separating the associated housingend into two separate fluid chambers 316 and 3.18, and partition 314forming similar chambers 32% and 322 in the opposite end of the housing.

The above-described fluid chambers 316-322 communicate with the centralportion of the housing 3% through preferably rectangular openingscommonly desig nated at 324 formed in generally V-shaped partitionsgenerally indicated at 326 and 32$. Similarly to the forms previouslydescribed, partitions 326 and 328 permit the fluid to enter the fluidchambers only through the openings 324, which are adapted to bealternately closed as will be hereinafter described.

Referring to FIGS. 19 and 20, the spray arm housing 36% is adapted to berotatably mounted on the center post and supporting structure thereforin generally the same manner as that previously described, and to theextent of 'such similarity, such structure will not be redescribed. The'centerpost, generally designated at 330, structurally varies from thatpreviously described in that an annular flange 532 is formed therewithwhich is adapted to seat on the center post mounting member 334. Apreferably self-lubricating bearing 336 is press fit within the openingin the spray arm housing for rotatably mounting the spray arm on thecenter post. A similar bearing member 34% is provided for supporting theupper portion of the housing 3% about the center post. The spray armhousing is maintained on the center post structure by means of mountingbolt 341 which extends through the center post 330 into engagement witha threaded opening in mounting member 334 as previously described.

Referring now to the means for controlling the fluid flow into thechambers File-322, a pair of V-shaped valves 342 and 344 are mountedadjacent the partitions 325 and 328 for alternately closing the opening324. The valves 342 and 344 are identically constructed and valve 344,e.g., comprises spaced legs 346 and 348 which converge to a cylindricalvalve body portion 356, the latter having mounted thereon at oppositeends mounting pins 352 and 354 which extend into openings providedtherefor in the housing sections 392 and 304. The ends of thecylindrical body portion 55% are formed fiat and smooth for sealingengagement with the opposed housing surfaces. Although not critical, theangle between the legs 346 and 343 is approximately one-half the anglebetween the sides of the partition 328, as seen in FIG. 17. The valve34-4 is alternately positioned, as indicated by solid and dashed lines,over oppositely disposed openings 324 for alternating fluid flow tochambers 329 and 322, respectively.

A valve arm generally designated at 360 is rotatably mounted on thecenter post 33%, the valve arm including a central mounting portion 362,oppositely directed arms 364 and 366 and downwardly turned flanges368374 at the outer ends of the arms. As best shown in FIG. 17,

the flange 363-374 contact the legs of'the Valves 342 and 344 wherebysuch valves can be pivoted to their alternate positions under conditionsto be described below.

A clutch spring 376 is telescoped over the center post 330 and the upperconvolution thereof has an end which extends through an opening in adownwardly depending fiange 356 of the valve arm 36% whereby the clutchspring rotates with the valve arm. The end of the bottom convolution ofthe clutch spring 376 is mounted on a clutch plate generally indicatedat 373, the latter being provided with'upwardly extending tabs 38% whichcan be crimped over such lower spring end to hold the same in place. Theradially outer peripheral ring 382 of the clutch plate 378 seats uponthe cylindrical ring portion 338 of the center post as clearly shown inPEG; 20, and the plate further includes a hub portion 334 telescopedaround the cylinder 358 of the center post. A plurality of spiderconnecting arms 3&6 serve to connect the peripheral ring 382 and the hub334, such arms not materially ailecting fluid flow upwar ly through thecenter post. The clutch plate 373 is maintained in resilient engagementwith the ring 333 by the clutch spring 376, the latter being compressedwhen operatively mounted, the spring also functionin to rotatably couplethe clutch plate 378 to the valve arm 36% responsive to rotation of thelatter, as will be presently described.

Referring now to the operation of the form shown in FIGS. 16-20, andpresuming that the valve arm 36% is in its FIGS. 16 and 17 position atthe initiation of the cycle, fluid introduced to the housing upwardlythrough the center post structure will enter the fluid chambers 316 and322, the valves 342 and 344 closing the openings 324 V to the chambers318 and 320. The fiuidemanating from V the drive jets 3G8 communicatingwith the chambers 316 and 322 will effect rotation of the spray arm 3%in a clockwise rotation, as viewed and indicated in FIG. 16. During theinitial stage of rotation, the upper convolutions of the clutch spring3'76 will rotate relative to the lower convolutions thereof due to thecompressive loading on the spring, thereby effecting a torque build-upin the spring. After a predetermined degree of rotation, the torquebuild-up in the spring 376 will exceed the compressive force of thespring whereby the clutch plate 378 will be carried with the clutchspring. To avoid excessive torque build-up in the spring 376 an upwardlyextending stop member 382 is provided on the bottom housing section 304which is adapted to engage a peripheral flange 384 formed on the ring382 of the clutch plate to limit the rotation. of the valve arm 36%relative to the clutch plate to less than one revolution of the sprayarm. The torque buildup in the clutch spring 376 will never exceed inforce the fluid pressure force acting on the valves 342 and 344 wherebysuch torque is unable during that cycle to effect rotation of the valvesaway from their FIG. 17, solid line position. However, upon a drop inpressure within the housing, such torque loading of the clutch springwill effect rotation of the valve arm 36%) in the opposite directionabout the axis of the center post. The legs 368-374 will, as a result ofsuch movement, carry the valves 342 and 344 to a position adjacent theoppositely disposed openings 324 associated with the chambers 316 and322.

As the fluid pressure builds up at the beginning of the next cycle, thefluid will be directed into the chambers 318 and 329; and, as describedabove, the clutch spring 376 will become torque loaded whereby the valvemechanism will automatically reverse the direction of rotation of thespray arm at the end of such next cycle.

Although there has been described only one such spray arm, it will ofcourse be understood that a similar spray arm can be provided rotatablymounted in the upper portion of the washing chamber in a similar manneras the previously described spray arm 70.

at both ends of the spray arm responsive to a drop in fluid pressure.Where the spray arm structure and center post and supporting structuretherefor is identical with that preciously described in the form shownin FIGS. 16-20, the same reference numerals have been applied. In theFIGS. 21 and 22 form, the valve mechanism comprises a valve armgenerally designated at 3% rotatably supported about the center postcylinder 358. The valve arm 3% has formed on each opposed end thereofguide members 392- and 39 which are adapted to embrace ball valves 396and 398, respectively, and guide the movement thereof between opposedcircular openings 4% in each partition 326 and 328. Curved verticalwalls 4'52 and 494 are provided for preventing the ball valves 396 and398, respectively, from moving away from the guide members 392 and 394,respectively. Although not illustrated, upwardly extending projectionsmay be provided on the spray arm housing for preventing dead centerpositioning of the balls 3% and 3%..

The means for controlling the pivotal movement of the valve arm 3% isidentical with that previously described in the PIGS. 16-20 form,comprising clutch spring 376 and clutch plate 373. The operation of theform shown in FIGS. 21 and 22 is likewise similar to the operation ofthe FIGS. 16-20 form. Assuming the ball valves E o and 393 to be intheir PEG. 21 position, fluid entering the housing will be directed tothe fluid chambers 316 and 3 2 whereby the spray arm will be rotatedreactively in a clockwise direction. The clutch spring 376 will becometorque loaded as above described subsequent to rotation of the spray armand will effect a coupling or carrying of the clutch plate 378therewith, as previously described. The torque loading of the clutchspring 376 in the direction opposite to rotation of the spray arm willnot be effective to pivot the valve arm 3% however, due to the fluidpressure'within the housing. When the fluid pressure within the housingdrops at the end of the cycle, the torque loaded clutch spring 376 will,at a certain point, exceed the fluid pressure within the housingwhereupon the valve arm 3% will pivot whereby the guide members392 and3% will carry the ball valves 3% and 398 to a position adjacent theoppositely disposed openings In regard to the form of the inventionillustrated in FIGS. 21 and 22, it will be understood that a similarlyconstructed and operative spray arm can be provided in the region of thewashing chamber whereat the previously described spray arm is mounted.

It will be seen that in all forms of the invention the direction ofrotation of the spray arm is automatically reversed during the cleaningoperation, the number of such reversals depending, on the selectedoperative cycle. Each reversal is derived from or is set upautomatically by the rotation of the spray arm, such rotation in all ofthe disclosed forms serving to cock the valve actuating mechanism. Byreversing the spray arm, the dishes and utensils in the washing chamberare thoroughly cleaned to an extent not heretofore possible withpresently constructed directional spray arms. Such cleansing is furtherenhanced by the fact that the points of origin of the spray radiallyvary for each direction of rotation.

Other modes of applying the principle of the invention may be employed,change being made as regards the details described, provided thefeatures stated in any of the following claims or the equivalent of suchbe employed.

We therefore particularly point out and distinctly claim as ourinvention: j I

1. A reversing spray arm assembly comprising a reaction type spray armadapted to receive liquid under pressure, means for mounting said armfreely for rotation, said arm having orifices for discharging saidliquid therefrom, means for supplying liquid under pressure to saidspray arm, and means for reversing the direction of rota- A furthermodification is illustrated in FIGS. 21 and 22 tion of said spray arm inresponse to a drop in liquid pressure within said spray arm.

2. A reversing spray arm assembly comprising a reaction type spray armadapted to receive liquid under pressure, means for mounting said sprayarm freely for rotation, said spray arm having drive jet means forrotating said arm in both directions, means for supplying liquid underpressure to said spray arm, and valve means for reversing the directionof rotation of said spray arm in response to a drop in liquid pressurewithin said spray arm.

3. The combination of claim 2 wherein said spray arm is provided with atleast two drive jets, the drive jets being inclined upwardly andoutwardly respectively in opposite directions to provide for drive ofsaid spray arm in both directions. r

4. The combination of claim 2 wherein said spray arm is mounted adjacentthe bottom of a washing chamber formed with a central raised portionhaving an opening communicating with hose means, pump means connected tosaid hose means, center post means associated with said hose means, andmeans for rotatably mounting said spray arm on said center post means.

5. The combination of claim 4 further including actuating meansassociated with said center post for actuating said valve means.

6. A dishwasher comprising a washing chamber, pump means having an inletcommunicating with the bottom of said washer chamber, vertically spacedspray arms rotatably mounted in said washing chamber adjacent the bottomand relatively adjacent the top thereof, means for communicating theoutlet of said pump means with each of said spray arms for supplyingfluid under pressure to said spray arms for rota-ting the same, at leastone of said spray arms having drive jets selectively for driving saidone arm in both directions, and means in said one spray arm forreversing the direction of rotation of said spray arm responsive to adrop in fluid pres sure within said arm.

7. A dishwasher comprising a washing chamber, pump means having an inletcommunicating with the bottom of said washing chamber, a reaction typespray arm, means for rotatably mounting said spray arm in said chamber,the interior of said spray arm communicating with the outlet of saidpump means whereby the latter supplies fluid under pressure to saidspray arm for rotating the same, said spray arm being provided with alongitudinal partition in at least one end thereof, said partitionseparating said one end into two fluid chambers, one of said chamberscommunicating with a series of radially spaced drive jet openings insaid spray arm directed upwardly and outwardly relative to saidassociated chamber, the other of said chambers communicating with aseries of radially spaced, oppositely directed drive jet openings insaid spray arm, whereby fluid supplied to said one chamber will effectrotation of said spray arm in one direction and fluid supplied to saidother chamber will efiect rotation of said spray arms in the oppositedirection, and valve means alternately directing fluid in said spray armto said chambers thereby reversing the direction of rotation of saidspray arm, said valve means being operable in response to a drop influid pressure within said spray arm.

8. The combination of claim 7 further including a second partitionwithin said spray arm, said second partition defining the radially innerlimits of said chambers, said second partition having a pair of openingsformed therein, each of said openings communicating respectively witheach of said chambers, said valve means alternately closing each of saidopenings responsive to a drop of pressure withinsaid spray arm, wherebyfluid directed to said spray arm is alternately directed to saidchambers for alternately reversing the direction of rotation of saidspray arm.

9. The combination of claim 8 wherein said valve means comprises a ballmember alternately seatable in said openings in said second partition bythe fluid pressure within said spray arm, said ball being supported formovement between said openings by a bar pivotally mounted within saidarm adjacent said second partition, a bar actuator pivotally mounted onthe bottom of said spray arm and engaging the bottom of said bar, saidbar actuator being biased upwardly during rotation of said spray arm bya stationary pin actuating means secured to the means for mounting saidspray arm, said bar tending to unseat said ball from the associatedopening, the force of said bar on said ball being ineffective to unseatsaid ball when the pressure of the fluid supplied to said spray armexceeds a predetermined amount, said bar effecting such unseating whenthe fluid pressure drops below such predetermined amount, the ball whenunseated rolling by gravity down said bar into position adjacent theother opening in said second partition.

10. The combination of ciaim 8 wherein said valve means comprises a pairof angularly disposed valve plates pivotally mounted in said spray arm,each of said plates being seatable on said second partition for coveringthe associated opening therein, resilient means biasing said valve plateaway from such seating position during rotation of said spray arm, suchbiasing effect being ineflective to unseat said valve plate due to thefluid pressure acting to seat said valve plate, stationary actuating pinmeans mounted on said mounting means for said spray arm for biasing saidresilient means during rotation of said spray arm, said resilient meansbeing effective responsive to a drop of pressure within said spray armto pivot said valve plate away from seated engagement with said secondpartition and to move the other of said valve plates adjacent the otheropening in said second partition.

11. A dishwasher comprising a washing chamber, pump means having aninlet communicating With the bottom of said washing chamber, a reactiontype spray arm, means for rotatably mounting said spray arm in thebottom of said chamber, said spray arm being provided with oppositelydirected drive jet openings in each end thereof to accommodate rotationof said spray arm in both directions, said spray arm communicating withthe outlet of said pump means whereby the latter supplies liquid underpressure to said drive jets for reactively rotating said arm, and valvemeans in said spray arm for controlling liqiud flow within said sprayarm for effecting reversal of the direction of rotation thereofresponsive to a drop in the liquid pressure within said spray arm.

12. The combination of claim 11 wherein each end of said spray arm isprovided with a longitudinal and generally transverse partition whichdefine first and second liquid chambers, a row of radially spaced drivejet openings communicating with said first liquid chamber for rotatingsaid spray arm in one direction, and a row of radially spaced,oppositely directed drive jet openings communicating with said secondliquid chamber, said transverse partition being formed with openings tosaid first and second liquid chambers, said valve means alternatelyclosing said openings whereby liquid supplied to said spray arm isdirected alternately to said first and second liquid chambers.

13. The combination of claim 12 wherein said valve means is operativelyconnected to biasing means for biasing said valve means during rotationof said spray arm away from a first position closing the respectiveopening to a second position adjacent the respective openings in theother liquid chambers, such biasing being ineffective to actuate saidvalve means when the liquid pressure within said spray a-rm exceeds apredetermined amount, the dropping of liquid pressure within said armbelow said predetermined amount effecting movement of said valve meansby said biasing means to said second position whereby subsequent supplyof liquid under a pressure in excess of said predetermined amounteflects rotation of said spray arm in the opposite direction.

14. The combination of claim 13 wherein said biasing means comprises acoil spring operatively connected at one end to said valve means and atits other end to a clutch plate seated on said mounting means for saidspray arm, said coil spring biasing said clutch plate into such seatedposition, initial rotation of said spray arm eifecting rotation of saidvalve means and the upper end of said coil spring relativeto the lowerend thereof thereby effecting a torque buildup therein, such torque uponfurther rotation of said spray arm overcoming the force of said springand efiecting rotation of said clutch plate relative to said mountingmeans, such torque buildup biasing said valve means away from said firstposition but being ineffective in so doing until the fluid pressurewithin said spray arm drops below said predetermined amount.

15. The combination of claim 14' further including stop means mounted onsaid spray arm for limiting the relative rotation between said spray armand said valve means, and said clutch plate thereby limiting the torquebuildup in said coil spring.

16. The combination of claim 14 wherein said valve means comprises apair of V-shaped valve members piv-. otally mounted in said spray arm,each valve member being mounted respectively adjacent the generallytransverse partitions, the legs of said valve members alternatelyclosing the openings to said first and second liquid chambers, andvalvearm means mounted in said spray arm and disposed in operativeengagement with both of said valve members for simultaneously movingsaid valve members upon a drop in liquid pressure within said spray arm.

17. The combination of claim 14 wherein said valve means comprises avalve arm rotatably supported within said spray arm and ball valvemembers carried at the opposite ends of said valve arm, each of saidball valves alternately closing said openings to said first and secondliquid chambers, said valve arm being operatively connected to said coilspring, whereby said valve arm carries said ball valves to aposition'adjacent the other of said openings responsive to a drop ofliquid pressure within said spray arm.

18. The combination of claim 17 wherein said valve arm is provided atopposite ends thereof with guide members which embrace the ball valvesand guide the movement thereof between the openings in said generallytransverse partition, and means for maintaining said ball valves withinsaid guide means.

19. A dishwasher comprising a washing chamber, a reaction type spray armrotatably mounted in said washing chamber, pump means for supplyingliquid under pressure to said spray arm for rotating the same, saidspray arm having four liquid chambers for selectively receiving liquidfrom said pump, each of said liquid chambers communicating with thewashing chamber through a plurality of drive jet openings formed in thespray arm, valve means in said spray arm for alternately directingliquid to a first pair of said liquid chambers for rotating said sprayarm in one direction, and to a second pair of said liquid chambers forrotating said spray arm in the opposite direction.

20. A reversing spray arm assembly comprising a reaction type spray armadapted to receive liquid under pressure, means for mounting said sprayarm freely for rotation, drive jet means for rotating the arm as aresult of discharge of pressure liquid therethrough, said drive jetmeans having two conditions of adjustment respective- 1y for thusrotating the arm in both directions, actuator mechanism for causing thedrive jet means to be adjusted from the condition producing rotation inone direction to the position causing the arm to rotate in the oppositedirection, said actuating means being subjected to the influence of thepressure liquid and restrained thereby from actuating the drive jetmeans when the pressure is above a ore-determined value, and meansresponsive to rotation of the arm in one direction for biasing theactuating means to adjust the drive jet means for rotation of the arm inthe reverse direction, whereby a drop in the pressure of the liquidbelow said pre-determined value results in automatic adjustment of thedrive jet means by the actuating mechanism to the position for suchreverse direction.

21. A reversing spray arm assembly comprising a rotatably mountedreaction spray arm, means for supplying liquid under pressure to saidspray arm, said spray arm being provided with first drive jet means forrotating said spray arm in one direction and second drive jet means fordriving said spray arm in the opposite direction, first chamber meanscommunicating with said first drive jet means for supplying liquid underpressure thereto and second chamber means communicating with said seconddrive jet means for supplying liquid under pressure thereto, valvingmechanism responsive to fluctuations in liquid pressure within saidspray arm for reversing the direction of rotation thereof, said valvingmechanism comprising a valve arm disposed within said spray arm and atleast one valve member adapted to be moved by said valve arm foralternately directing the liquid to said first and second chamber meansfor respectively rotating said spray arm first in said one direction andthen in said other direction.

22. A reversing spray arm assembly comprising a rotatably mountedreaction spray arm, means for supplying liquid under pressure to saidspray arm, partition means within said spray arm defining first andsecond chamber means for alternately receiving theliquid under pressure,said spray arm being provided with first drive jet means communicatingwith said first chamber means for rotating said spray arm in onedirection and second drive jet means communicating with said secondchamber means for rotating said spray arm in the opposite direction,valving mechanism responsive to fluctuation in the liquid pressurewithin said spray arm for reversing the direction of rotation thereof,said valving mechanism comprising a valve arm rotatably mounted in saidspray arm and valve members adapted to be moved by said valve arm foralternately directing liquid to said first and second chamber means forrespectively rotating said spray arm first in said one direction andthen in said opposite direction.

References Cited by the Examiner UNITED STATES PATENTS CHARLES A.WILLMUTH, Primary Examiner,

1. A REVERSING SPRAY ARM ASSEMBLY COMPRISING A REACTION TYPE SPRAY ARMADAPTED TO RECEIVE LIQUID UNDER PRESSURE, MEANS FOR MOUNTING SAID ARMFREELY FOR ROTATION, SAID ARM HAVING ORIFICES FOR DISCHARGING SAIDLIQUID THEREFROM, MEANS FOR SUPPLYING LIQUID UNDER PRESSURE TO SAIDSPRAY ARM, AND MEANS FOR REVERSING THE DIRECTION OF ROTATION OF SAIDSPRAY ARM IN RESPONSE TO A DROP IN LIQUID PRESSURE WITHIN SAID SPRAYARM.